气候变化领域集成服务门户(CCPortal): Molecular bases of an alternative dual-enzyme system for light color acclimation of marine Synechococcus cyanobacteria

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DOI	10.1073/pnas.2019715118
	Molecular bases of an alternative dual-enzyme system for light color acclimation of marine Synechococcus cyanobacteria
	Grébert T.; Nguyen A.A.; Pokhrel S.; Joseph K.L.; Ratin M.; Dufour L.; Chen B.; Haney A.M.; Karty J.A.; Trinidad J.C.; Garczarek L.; Schluchter W.M.; Kehoe D.M.; Partensky F.
发表日期	2021
ISSN	00278424
卷号	118 期号:9
英文摘要	Marine Synechococcus cyanobacteria owe their ubiquity in part to the wide pigment diversity of their light-harvesting complexes. In open ocean waters, cells predominantly possess sophisticated antennae with rods composed of phycocyanin and two types of phycoerythrins (PEI and PEII). Some strains are specialized for harvesting either green or blue light, while others can dynamically modify their light absorption spectrum to match the dominant ambient color. This process, called type IV chromatic acclimation (CA4), has been linked to the presence of a small genomic island occurring in two configurations (CA4-A and CA4-B). While the CA4-A process has been partially characterized, the CA4-B process has remained an enigma. Here we characterize the function of two members of the phycobilin lyase E/F clan, MpeW and MpeQ, in Synechococcus sp. strain A15-62 and demonstrate their critical role in CA4-B. While MpeW, encoded in the CA4-B island and up-regulated in green light, attaches the green light-absorbing chromophore phycoerythrobilin to cysteine-83 of the PEII α-subunit in green light, MpeQ binds phycoerythrobilin and isomerizes it into the blue light-absorbing phycourobilin at the same site in blue light, reversing the relationship of MpeZ and MpeY in the CA4-A strain RS9916. Our data thus reveal key molecular differences between the two types of chromatic acclimaters, both highly abundant but occupying distinct complementary ecological niches in the ocean. They also support an evolutionary scenario whereby CA4-B island acquisition allowed former blue light specialists to become chromatic acclimaters, while former green light specialists would have acquired this capacity by gaining a CA4-A island. © 2021 National Academy of Sciences. All rights reserved.
英文关键词	Light regulation; Marine cyanobacteria; Photosynthesis; Phycobilin lyase; Phycoerythrin
语种	英语
来源期刊	Proceedings of the National Academy of Sciences of the United States of America
文献类型	期刊论文
条目标识符	http://gcip.llas.ac.cn/handle/2XKMVOVA/180487
作者单位	Ecology of Marine Plankton Team, UMR 7144, Adaptation and Diversity in the Marine Environment, Station Biologique, Sorbonne Université, CNRS, Roscoff, 29680, France; Department of Biological Sciences, University of New Orleans, New Orleans, LA 70148, United States; Department of Chemistry, University of New Orleans, New Orleans, LA 70148, United States; Department of Biology, Indiana University, Bloomington, IN 47405, United States; Department of Chemistry, Indiana University, Bloomington, IN 47405, United States
推荐引用方式 GB/T 7714	Grébert T.,Nguyen A.A.,Pokhrel S.,et al. Molecular bases of an alternative dual-enzyme system for light color acclimation of marine Synechococcus cyanobacteria[J],2021,118(9).
APA	Grébert T..,Nguyen A.A..,Pokhrel S..,Joseph K.L..,Ratin M..,...&Partensky F..(2021).Molecular bases of an alternative dual-enzyme system for light color acclimation of marine Synechococcus cyanobacteria.Proceedings of the National Academy of Sciences of the United States of America,118(9).
MLA	Grébert T.,et al."Molecular bases of an alternative dual-enzyme system for light color acclimation of marine Synechococcus cyanobacteria".Proceedings of the National Academy of Sciences of the United States of America 118.9(2021).